The DNS server implementation, for PKI-based authentication, must implement a local cache of revocation data to support path discovery and validation in case of the inability to access revocation information via the network.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-205205	SRG-APP-000401	SRG-APP-000401-DNS-000051	SV-205205r982028_rule	2024-07-02	4

Description
Without configuring a local cache of revocation data, there is the potential to allow access to users who are no longer authorized (users with revoked certificates). SIG(0) is used for server-to-server authentication for DNS transactions, and it uses PKI-based authentication. So, in cases where SIG(0) is being used instead of TSIG (which uses a shared key, not PKI-based authentication), this requirement is applicable.

Description

Without configuring a local cache of revocation data, there is the potential to allow access to users who are no longer authorized (users with revoked certificates). SIG(0) is used for server-to-server authentication for DNS transactions, and it uses PKI-based authentication. So, in cases where SIG(0) is being used instead of TSIG (which uses a shared key, not PKI-based authentication), this requirement is applicable.

ℹ️ Check
Review the DNS server implementation configuration to determine if the DNS server, for PKI-based authentication (i.e., SIG(0)), implements a local cache of revocation data to support path discovery and validation in case of the inability to access revocation information via the network. If the DNS server does not implement such a cache of revocation data, this is a finding.

✔️ Fix
Configure the DNS server, for PKI-based authentication, to implement a local cache of revocation data to support path discovery and validation in case of the inability to access revocation information via the network.